The brains were collected by the Medical Research Council Sudden Death Brain and Tissue Bank, Edinburgh, UK47, and the Sun Health Research Institute an affiliate of Sun Health Corporation, USA48. Ten brain regions were sampled per individual for RNA analyses. The regions studied were cerebellar cortex, frontal cortex, hippocampus, inferior olivary nucleus (sub-dissected from the medulla), occipital cortex, putamen (at the level of the anterior commissure), substantia nigra, temporal cortex, thalamus (at the level of the lateral geniculate nucleus) and intralobular white matter. The choice of brain regions was driven by relevance to human disease and previous evidence to suggest high variance in expression profiles18,49,50.
